Gina Solomon, M.D., M.P.H.

21983 1987

3

1) Health disparities are linked to social factors and environmental hazards2) Significant inequalities exist in exposures to environmental hazards 3) Intrinsic biological and physiological factors can modify environmental hazards4) Extrinsic social vulnerability factors at the individual and community levels can amplify the effects of environmental hazards

Solomon G, Morello-Frosch R, Zeise L, Faust J. Cumulative Environmental Impacts: Science and Policy to Protect Communities. Annual Review of Public Health 37: 14.1-14.14, 2016.

Solomon GM, Faust JB, Morello-Frosch, R, Zeise, L. Integrating environmental justice into public health: approaches for understanding cumulative impacts. Front Public Health Serv Sys Res 5(5):9–14, 2016. DOI: https://doi.org/10.13023/FPHSSR.0505.02.

McHale CM, Osborne G, Morello-Frosch R, Salmon A, Sandy MS, Solomon G, Zhang L, Smith MT, Zeise L

• Difficult to correct environmental injustice without measuring it.

• How can we measure cumulative impacts?

• A tool should be:• Participatory• Allow comparisons

across time and space• Semi-quantitative

Context • Project-, policy-, program-, chemical- or plan-based decision (e.g., identify consequences of a specific proposal or activity)

• Geography- or population-based decision (e.g., identify overburdened areas or populations for purposes of prioritizing allocation of resources)

Stressors • Chemical stressors (e.g., pollutants in air, water, soil, food, products)• Biological stressors (e.g., internal and external microbiome)• Social stressors (e.g., discrimination, poverty, violence)• Physical stressors (e.g., noise, radiation, housing quality)

Vulnerability • Intrinsic factors (e.g., age, existing health conditions, genome)• Extrinsic factors (e.g., socioeconomic vulnerability, access to health

care)

Analytic Dimensions for Cumulative Impacts Analysis

Approach Quantitative? Chemical/ Nonchemical Participatory? Facilitates

comparisons?

Biomonitoring Yes Chemical Potentially Yes, exposure only

Cumulative Risk Assessment

Yes, generally Chemical No, generally Yes

Ecological Risk Assessment Potentially Both Potentially Generally no

Health Impact Assessment No, generally Both Yes, very Generally no

Burden of Disease/DALY Yes, very Both No Yes

Mapping Semi- Both Yes, potentially Yes

Biomonitoring

Health Risk Assessment

Level of Community Engagement

Quantitative

Cumulative Impacts Assessment Tools: Levels of Community Engagement

Inform/ConsultNone Collaborate/Empower

Qualitative

Burden of Disease/

DALYs

An

alyt

ical

Met

hod

Cumulative Impacts Mapping

Health Impact Assessment

Ecological Risk AssessmentSemi-

Quantitative

Xx

• Measures hundreds of chemicals in people• Can compare with other communities or national averages• Measurement of change over time (worse or better?)• (New) Ability to do non-targeted testing

But……

• Some chemicals can’t be biomonitored• Can’t identify the source of exposure• Doesn’t evaluate intrinsic vulnerability or extrinsic non-chemical

stressors

Chemical groups (PCBs, dioxins, PAHs, organophosphate pesticides)

Chemical mixtures (e.g., diesel exhaust) Exposures + intrinsic vulnerabilities“Exposome” (e.g., all exposures) Exposures + non-chemical stressorsAll exposures + intrinsic vulnerabilities + non-

chemical stressors

New Technologies to Measure Exposure

Future: Biological Markers of Health

•Allostatic Load•Telomere Length•Epigenetic Changes

Walker AJ, et al. Front. Psych, April 2014

Allostatic Load (“Toxic Stress”)Multi-System Response to Chronic Stress:

Primary: Stress hormones (cortisol, epinephrine, norepinephrine, DHEA)

Secondary: Inflammation (C-reactive protein, TNF, IL-6), blood pressure, heart rate variability, insulin/glucose, cholesterol/triglycerides, waist/hip ratio

Tertiary: Cardiovascular disease, neurodegenerative disease, cancer, etc.

Telomere Length

Accelerated telomere shortening is associated with early onset of many diseases, including coronary heart disease, heart failure, diabetes, cancer, and osteoporosis.

Causes of Telomere Shortening

• Age• Genetic factors• Socioeconomic status• Stress• Exercise• Smoking• Diet (quantity and quality)• Anti-oxidants• Occupational exposures • Environmental exposures (especially air pollution)

Epigenetics• Changes in organisms caused by modification of gene expression

rather than alteration of the genetic code itself.

Genetically Identical Mice

Future: Neighborhood-Specific Epigenome

Olden K, et al. Am J Public Health. 2014 October; 104(10): 1816–1821.

Conclusion

• Existing approaches to cumulative impacts all have limitations• Don’t include all exposures, intrinsic, and extrinsic stressors• Not very quantitative• Technical and hard for communities to engage

• Newer approaches are emerging• Better exposure measurement• Better markers of toxic stress (allostatic load)• Better markers of overall health (telomere length)• Neighborhood markers? (epigenome)

• Need to make decisions now and be nimble as new tools emerge